Pope Benedict XVI has appointed Bishop Gerhard Ludwig Müller of Regensburg as the new prefect of the Congregation for the Doctrine of the Faith, the Vatican announced today.

Bishop Müller replaces Long Beach, Ca.-born Cardinal William J. Levada, 76, who is stepping down on grounds of age. Bishop Müller also takes over Cardinal Levada's other responsibilities as president of the Pontifical Commission "Ecclesia Dei", the Pontifical Biblical Commission, and the International Theological Commission.

The new CDF prefect has been elevated to archbishop and will probably be made a cardinal at the next consistory.

The appointment of the 64 year-old bishop has been speculated for some time, with the German press reporting it as almost certain over the past few days.

Originally from Mainz in central Germany, Bishop Müller is already a member of the CDF and highly regarded in Rome. A professor of dogmatic theology, he specializes in defending faith and morals, is a prolific author, and has had a dogmatic textbook translated into several languages. He has a reputation among many as a defender of Catholic orthodoxy, and is also an expert on ecumenism as well as an accomplished scholar of liberation theology. Some traditionalists have voiced concern about some of his views, however, arguing he has not shown strong enough Catholic stances.

A personal friend of the Pope, the bishop won accolades for his organisation of the Holy Father’s visit to Regensburg in 2006. He has also been compiling the collected works of Joseph Ratzinger through the “Pope Benedict XVI Institute”, an organisation he founded in Regensburg in 2008.